10/30/13, Wednesday
Post date: Oct 31, 2013 12:20:8 PM
Bell Ringer
What is periodic motion?
Activities
Introduction to springs
Hooke's law mini-lab - due tomorrow
For each of two different springs, do the following:
Stretch the spring using a force scale. Record how far the spring was stretched, and how much force was required. Stretch a different amount and repeat for 10 data points.
Make a graph of F (in Newtons) vs. X (in meters)
Fit a line to your data
Calculate the slope of this line. The slope represents k, the spring constant for each spring
Hooke's Law
Fspring = - k x
The amount of force a spring applies to an object it is attached to is directly proportional to, and in the opposite direction as, the spring's displacement from its relaxed position
Page 371: 1-4 for practice
Introduction to simple harmonic motion
SHM is a special case of periodic motion
SHM is caused by a restoring force (a force that always pushed the object back toward its equilibrium position) which is proportional to displacement from equilibrium position
Examples of SHM:
A mass hanging from a spring
A pendulum
Practice
Page 371: 1-4
Assignments
Finish Hooke's Law Mini-Lab (due tomorrow)